The present invention generally pertains to irradiation systems that utilize a conveyor system for transporting articles through a target region scanned by radiation from a radiation source and is particularly directed to (a) an improvement in shielding the loading and unloading areas of such an irradiation system from radiation derived from the radiation source and (b) an improvement in reorienting the articles for retransportation through the target region in order to enable the articles to be irradiated from opposite sides.
A prior art irradiation system that utilizes a conveyor system for transporting articles through a target region is described in U.S. Pat. No. 5,396,074 to Peck et al. In such prior art system, the radiation source and the conveyor system are disposed in a room having concrete walls, wherein such concrete walls and additional concrete walls defining an angled passageway to the room shield loading and unloading areas located outside of the room from radiation derived from the radiation source.
A system for reorienting the articles for retransportation through the target region also is described in U.S. Pat. No. 5,396,074 to Peck et al. Such reorienting system is quite complex in that it includes a gear rack disposed adjacent a reroute conveyor system that transports the articles from a position on a primary conveyor system located past the target region in the direction of movement of the primary conveyor system to a position on the primary conveyor system located before the target region in such direction of movement, and a rotatable collar mechanism on an article carrier, wherein the rotatable collar mechanism interacts with the gear rack in such a manner as the article carrier is being transported past the rack by the reroute conveyor system as to reorient the article carrier by 180 degrees.